CMF / CRF Details

CMF ID: 78

Install changeable speed warning signs for individual drivers

Description:

Prior Condition: No Prior Condition(s)

Category: Advanced technology and ITS

Study: Handbook of Road Safety Measures, Elvik, R. and Vaa, T., 2004

 
Star Quality Rating: 4 Stars
Crash Modification Factor (CMF)
Value: 0.54
Adjusted Standard Error:
Unadjusted Standard Error: 0.1
Crash Reduction Factor (CRF)
Value: 46   (This value indicates a decrease in crashes)
Adjusted Standard Error:
Unadjusted Standard Error: 10
Applicability
Crash Type: All
Crash Severity: All
Roadway Types: Not specified
Number of Lanes:
Road Division Type:
Speed Limit:
Area Type: Not specified
Traffic Volume:
Average Traffic Volume:
Time of Day:
If countermeasure is intersection-based
Intersection Type:
Intersection Geometry:
Traffic Control:
Major Road Traffic Volume:
Minor Road Traffic Volume:
Average Major Road Volume :
Average Minor Road Volume :
Development Details
Date Range of Data Used:
Municipality:
State:
Country:
Type of Methodology Used: Meta-analysis
Other Details
Included in Highway Safety Manual? Yes. HSM lists this CMF in italics font to indicate that it has a lower reliability than bold font CMFs since it has an adjusted standard error of 0.2 to 0.3.
Date Added to Clearinghouse: Dec-01-2009
Comments: